Manipulation of the electronic and photovoltaic properties of materials based on small push-pull molecules by substitution of the arylamine donor block by aliphatic groups

摘要

Push-pull molecules with an arylamine donor block connected to a dicyanovinyl acceptor via a thienyl π-conjugating spacer have been synthesized in order to analyze the effects of replacing an outer phenyl ring of the triphenylamine (TPA) block of a reference compound by methyl, hexyl, heptafluoropentyl and dioxaoctyl groups. Optical, electrochemical and X-ray diffraction data show that these substitutions have minor influence on the energy levels of the molecule but exert a considerable effect on the structure, optical, electrical and photovoltaic properties of the resulting materials.